Duraspark II-ish Starting Issue?

Hey all.  I ran this by folks on another forum and got some great troubleshooting advice but I'm still getting stuck so I bring it to you, the bullnose experts for guidance!  First a recap of what is happening and what I've done.  One caveat, I'm EXTREMELY novice with electrical wiring.  Trying to chase these wires gives me anxiety!:

1984 Bronco, 351W, C6.  When purchased back in Feb/March I test drove the truck, started fine (twice, once to test drive, the other to load it on the trailer) and then brought it home.  Over the course of a few days, it would intermittently not start.  No discernable sounds other than the faint click of the starter.  I wasn't too worried because I'd be parking it to do some upgrades (not related).  

Fast forward to today, I'm ready to figure out the starting issue.  The previous owner had installed what I now know to be a PMGR starter (the one with the solenoid attached?) and had wired the ignition without utilizing the fender mounted solenoid (the black one with 4 posts?) so it just sits there empty.  As best I can tell, the wiring runs straight from the battery (large positive cable only) directly to the starter and there are two brown-ish wires with some sort of embedded fuse on them hooked to the same post on the starter (not sure where those originate from) and then what I think is the ignition wire (smaller red wire) on the other post of the starter.  

The truck will fire every now and then.  And I mean every now and then.  Maybe once or twice every 50 times I turn the key, randomly.  When it does, it fires up great.  Then nothing.  Just a click of the starter.  

I'd like to get the wiring back to "original" as required as I'm fairly certain this is my issue.  Awhile back I started shotgunning fixes at it (I know, I know) and here is what has been replaced:

- Key lock cylinder (key was sticking in "start"
- Ignition Switch
- Ignition Module
- Starter
- Battery Tested good/tried 2nd battery as well
- Cleaned grounding areas to ensure good connections

I have read the PMGR how to page on this forum and I'm ready to give that a try, but I am not 100% sure where to run those additional (smaller) wires FROM and where to tie them into on the fender mounted solenoid (if at all).  The larger battery cable seems simple enough.

Also, would the way the previous owner has it wired now negatively effect the truck how I've described?  Is there some electrical load being effected by having everything wired directly to the starter?  The only other thing I can think of that I haven't tried is the neutral safety switch. Keep in mind I AM getting a one-click response from the starter when I turn the key and every once in awhile (hardly ever) it starts right up.

The problem is twofold, first, the ignition switch on the older Fords is not capable of handling the current draw of the PMGR starter. The second part is because of that the switch is probably bad.

The first application I had with a factory PMGR starter was a 1990 Lincoln Town Car we owned. It had the PMGR starter, and used a Bosch relay underhood to engage it.

The way I and others have done for the PMGR is to retain the standard Ford relay and wire it with the original hot side (including the fusible links) on the front large post and the large cable to the starter also there. The existing red/blue wire from the starter terminal on the ignition switch goes to the "S" stud. The other large terminal is where the "trigger" wire to the solenoid goes.

If you don't want to mess with the big Ford relay, a weather proof Bosch relay can be used, but needs a weatherproof socket. A good source for both is Chrysler built minivans from the early to mid 90s, they have a row of them on the driver's side fender.

Thanks for the quick reply!  So, just to be sure I understand your wiring recommendation, (again, comfort level near zero ) is what you are describing like the picture below?



Also, so I completely understand and don't blow myself up, I take the existing smaller red wire that is connected to the starter, and connect that to the fender mounted relay on the "S" terminal (from wherever it originates from currently).  I take the two fusable (brown?) wires that are currently on the starter post with the + battery cable and connect those to the battery side post of the fender mounted relay (along with the + battery cable) from wherever they originate from currently.  Then i can take an additional smaller gauge wire(?) and connect it from the output side of the relay (as in pic below) and connect the other end to the smaller ignition terminal on the starter, where my existing small red wire is currently connected.  

Is this correct?  I could be totally off.  Also, this will help fix the issues with the PMGR starter/ignition switch?  I'm assuming my ignition switch is good since I'm having the same issues with the new switch installed as I did with the previous one, at least unless I'm missing something else.

Thanks in advance for your patience!  

Bill may be along in a bit, but I'm not sure your words match what the drawings show.

So let me say it in my words.  You'll have a large wire, the positive battery cable, from the battery to the front large terminal of the starter relay.  And from the same terminal you'll have a large wire down to the starter.  In addition, if the "two fusable (brown?) wires" are truly fuse links they will go on that same terminal.  What that does is provide power 100% of the time to the starter and the fuse links.

Then from the rear side of the starter relay, the other large terminal, you will have a smaller wire going to the small terminal on the starter.

The red/blue wire that comes from the ignition switch should already be hooked to the small front terminal of the starter relay.

Does that make sense?

Thanks Gary (and Bill)!!

I think so.  POS Battery cables (2) from batt to relay then relay to starter (same relay post).  

Then (this is where I’m getting really confused) I’ll need to figure out where the two fused links are originating from and move them to the same relay post as the batt cables, then route them to the same post on the starter as the pos batt cable (I’m not sure I’m correct there.  Or are you saying they go to the same terminal on the starter itself as they are in my original picture?)  OR, keep them from where they currently originate and end them on the same fender relay post as the large batt and starter cables

Next, the other smaller wire from relay to starter I understand.  I’ll have to make that one as it doesn’t exist on mine now.  

Last, the red/blue wire from the ignition switch.  The wire that is currently connected to my starter is only red (it’s the one on its own in my original picture) but could be spliced in somewhere with the red/blue so I’m assuming that’s the wire in question.

However, you said it should already be hooked to the small front terminal on the starter relay, but mine is not.  I have nothing connected to that fender mounted relay.  Should I move that wire from the starter to the terminal on the fender relay labeled “S”?

When I’m done, the four wires I have connected directly to the starter will be reduced to one large and one small cable (both from the relay) and the ignition wire and two fused links will end at my fender relay.  ....I think....

I know this is probably painful but I’d really like to be able to fix this one without giving up.  Even with the EVTM manual I’m lost.  

Your drawing is exactly correct sir. The fusible links are what go to the alternator and inside the cab, they are spliced onto the ends of what should probably be yellow 8 or 10 ga wires.

Good luck with it!

Thanks Bill! I was wondering where those wires connected to.  It’s hard to follow them w the mess of wires in there.  

So unless someone says otherwise it’s fused ends on the fender relay along with red ignition wire and two battery cables.  Then one battery cable to the starter and one smaller 8/10ga wire from fender relay to smaller starter terminal.  

So, how does this configuration help the ignition switch power the PMGR starter better than wiring everything straight to the starter?  Hoping this fixes my issues!

Re-reading your initial post and now I can start to see exactly what you’re saying for the routing (finally) and it appears to mirror what I’ve stated above, so this will be my project tomorrow!  I’ll report back hoping it helps crank this starter.  Thanks again!

It takes the load off the ignition witch so the switch does not have to carry the full starting amperage. Like this, it's only pulling enough amperage to energize the starting relay.

Thanks Frank!  I wish I was smarter on this stuff.  But that does make sense

Jason2215 wrote

So, how does this configuration help the ignition switch power the PMGR starter better than wiring everything straight to the starter?

Not the switch but rather the relay (fender mounted and often called a solenoid). The actual ignition switch mounted halfway down on the steering column doesn't know the difference between the standard starter and the PMGR. All it knows is what it takes to energize the fender mounted relay.
The PMGR takes the load off the fender mounted relay because now the relay doesn't need to carry the load of the actual starter. Only the solenoid down on the starter. This means the relay is only carrying a fraction of what it can carry and thus the idea is that it will last a LOT longer.

Regarding the fuse links, you shouldn't necessarily need to know where they go although it's always good info to have no doubt. Just saying there is no need to track them down through the harness(es). Only that they should be mounted to the same post on the fender mounted relay as the POS cable (as well as the large awg cable that goes to the starter).

Think of that post/stud as just a distribution point. The fuse links and even the larger awg cable going to the starter could just as well be connected directly to the POS battery terminal.

Speaking of the fuse links - could you add a photo of the fender mounted relay and all the wires around it that are or aren't connected? We should be able to give you some info on what they are for.

That's a great way to explain it, thank you!  And absolutely that would be great.  Here are a few pictures of different locations that may affect what's going on:






Feel free to offer any suggestions on anything you see.  It'll all eventually get touched I'm sure!

I read over the first post again after seeing the fender mounted relay (fmr) and it finally clicked with what was going on. Sorry, didn't get last night what Bill grasped right off the bat.

Hadn't ever thought about anyone moving everything down to the starter solenoid and foregoing the fender mounted relay. When you said nothing was hooked to it I read that as it was removed recently for diagnostics. That also make sense with the mention of added load on the ignition switch since the solenoid takes a lot more than the fmr. Again, sorry everyone for being late to the party.

Taking it in a multi step approach:

1. Ignore the stud on the starter solenoid with 3 wires (positive battery, 2 fuse links)
2. Remove the smaller red wire and move it to the S stud on the fmr. As mentioned earlier, it should be crimped to a red/blue wire when they extended it down there to the starter solenoid.
3. Run a wire from the battery positive to the far left hand stud on the fmr. We can talk about battery cable terminal options later but for this test you can loosen the clamp holding the wire (not the battery stud), insert a stripped end of wire in there and clamp it back. Then run this wire to the left hand stud. Again, I would not do this permanently. Use 8/10 awg for this. It may change later depending upon what is done with the fuse links.

Once that is done you can test the ignition switch and fmr. Nothing should be on the right hand stud except for the multimeter.
When not cranking, the right hand stud on the fmr should show no voltage. When cranking it should show full voltage. I would test this a number of times and report back.

Scott, I’m on it!  Just so we don’t have any confusion (on my part) left meaning the post closes to the firewall, not the front of the truck.  

Let's do numbers instead as left/right can get confusing.

I am referring to 1 and 2 for now. Please verify that 2 has an S near it. I haven't seen S and I swapped but always good to confirm.

The wire from the battery will go to 1.
The smaller red wire currently alone down on the starter solenoid will go to 2.
Nothing will be on 3.
Multimeter will go to 4 and ground.

Yes sir.  Back in a few.  Keeping the starter stud w the 3 wires as is.  

Ok, reading battery voltage to terminal 1.  When I put the meter on terminal 4 and ground, meter jumps all over (I’m no pro so if I have my meter on the wrong setting?)

When the car cranks, terminal 4 stays solid at 11.71.  Then when key is off it goes wild again.

FWIW, I can feel the fmr physically kick when key is turned.

Here’s what I’m using on the meter.  Battery is now pretty low after trying to crank it for days, I’m sure. It was 12.36 when I tested it 10 minutes ago.


Edit: wife left key in “on”.  Batt reads 12.24 now.

1. What values are you seeing 4 jump around to when the key is off?
2. If you check the voltage on 2 with the key off, what do you get?

Grounded and on terminal 2, I'm receiving steady 9.5 to 9.6v until the key is turned off, then back to 0.

The numbers on terminal 4 with no action is all over the place rapidly.  Into the hundreds, decimals under 1, etc.  I don't know if it's user error or what but my other readings all look normal.  I am grounding the black prong on the fmr bracket portion bolted to the fender for all these.

BTW, really appreciate all the help.  I'm excited to get this back to working order.

Interesting. I would expect higher than 9.6v on the R/Bl but I can check mine later. As you are seeing/feeling/hearing, that is enough to pull in the relay though.

What more concerns me is voltage on 4 with the key off. Since the next step is to run a new 8/10awg wire from 4 to the starter solenoid (the stud that original had the red wire that is now on 2), I don't want you doing that if there is any chance the starter could engage with the key off.

It's not uncommon for off the shelf fmr's to be bad or go bad quickly. You could disconnect 1 and check continuity between 1 and 4 but I think I'd just go pick up a new one.

I don't see that the fmr was replaced in the first post. Do you know the history of it? Possibly it going bad was the reason everything was moved to the starter solenoid?